package cn.shit;

import java.util.HashSet;
import java.util.Iterator;
import java.util.Scanner;
import java.util.Set;

public class SetTest {
    public static void main(String[] args) {
        Set<String> words = new HashSet<>(); // HashSet implements Set
        long totalTime = 0;
        try (Scanner in = new Scanner(System.in)){
            while (in.hasNext())
            {
                String word = in.next();
                long callTime = System.currentTimeMillis() ;
                words.add(word);
                callTime = System. currentTimeMillis() - callTime;
                totalTime += callTime;
            }
            Iterator<String> iter = words.iterator() ;
            for ( int i = 1 ; i <= 20 && iter.hasNext(); i++)
                System. out.println( iter.next ()) ;
            System. out.println(" . . .");
            System.out.println(words.size( ) + " distinct words. " + totalTime + " milliseconds. ") ;
        }
    }
}
